build: Add unit test target generation to cpp_library CMake util; Add tasks for building and running unit tests. (#26)

Co-authored-by: davidlion <[email protected]>

Author: Bill-hbrhbr

.github/workflows/unit-tests.yaml

@@ -61,6 +61,5 @@ jobs:
           command -v tar
           command -v task
 
-      # TODO: Change the task to run all unittests once any unittest is added. Until then we check
-      # that building the project succeeds.
-      - run: "task build:all"
+      - name: "Run unit tests"
+        run: "task test-all"

CMake/ystdlib-cpp-helpers.cmake

@@ -1,8 +1,12 @@
 # Adds a c++20 interface library in the subdirectory NAME with the target NAME and alias
 # NAMESPACE::NAME. Libraries with multiple levels of namespace nesting are currently not supported.
 #
+# If `BUILD_TESTING` is ON, build the unit tests specific to the current library, and link this
+# library against the unified unit test target for the entire `ystdlib-cpp`.
+#
 # @param NAME
 # @param NAMESPACE
+# @parms TESTS_SOURCES
 # @param [LIB_BUILD_INTERFACE="${PROJECT_SOURCE_DIR}/src"] The list of include paths for building
 # the library and for external projects that link against it via the add_subdirectory() function.
 function(cpp_library)
@@ -11,7 +15,10 @@ function(cpp_library)
         NAME
         NAMESPACE
     )
-    set(multiValueArgs LIB_BUILD_INTERFACE)
+    set(multiValueArgs
+        TESTS_SOURCES
+        LIB_BUILD_INTERFACE
+    )
     cmake_parse_arguments(arg_cpp_lib "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
 
     # TODO: Turn this into a function for handling other optional params that have default values.
@@ -24,6 +31,7 @@ function(cpp_library)
         set(arg_cpp_lib_LIB_BUILD_INTERFACE "${PROJECT_SOURCE_DIR}/src")
     endif()
 
+    # Build interface library
     add_library(${arg_cpp_lib_NAME} INTERFACE)
     target_include_directories(
         ${arg_cpp_lib_NAME}
@@ -32,4 +40,32 @@ function(cpp_library)
     )
     target_compile_features(${arg_cpp_lib_NAME} INTERFACE cxx_std_20)
     add_library(${arg_cpp_lib_NAMESPACE}::${arg_cpp_lib_NAME} ALIAS ${arg_cpp_lib_NAME})
+
+    if(BUILD_TESTING)
+        set(_UNIT_TEST_TARGET "unit-test-${arg_cpp_lib_NAME}")
+        add_executable(${_UNIT_TEST_TARGET})
+        target_sources(${_UNIT_TEST_TARGET} PRIVATE ${arg_cpp_lib_TESTS_SOURCES})
+        target_link_libraries(
+            ${_UNIT_TEST_TARGET}
+            PRIVATE
+                Catch2::Catch2WithMain
+                ${arg_cpp_lib_NAMESPACE}::${arg_cpp_lib_NAME}
+        )
+        target_compile_features(${_UNIT_TEST_TARGET} PRIVATE cxx_std_20)
+        set_property(
+            TARGET
+                ${_UNIT_TEST_TARGET}
+            PROPERTY
+                RUNTIME_OUTPUT_DIRECTORY
+                    ${CMAKE_BINARY_DIR}/testbin
+        )
+
+        # Link against unified unit test
+        target_sources(${UNIFIED_UNIT_TEST_TARGET} PRIVATE ${arg_cpp_lib_TESTS_SOURCES})
+        target_link_libraries(
+            ${UNIFIED_UNIT_TEST_TARGET}
+            PRIVATE
+                ${arg_cpp_lib_NAMESPACE}::${arg_cpp_lib_NAME}
+        )
+    endif()
 endfunction()

CMakeLists.txt

@@ -11,25 +11,33 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS
     FORCE
 )
 
-find_package(Catch2 3.8.0 REQUIRED)
-if(Catch2_FOUND)
-    message(STATUS "Found Catch2 ${Catch2_VERSION}.")
-else()
-    message(FATAL_ERROR "Could not find libraries for Catch2.")
-endif()
+option(BUILD_TESTING "If ON, unit tests will be built." ON)
 
 # Import CMake helper functions
 list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_LIST_DIR}/CMake)
+
+if(BUILD_TESTING)
+    find_package(Catch2 3.8.0 REQUIRED)
+    if(Catch2_FOUND)
+        message(STATUS "Found Catch2 ${Catch2_VERSION}.")
+    else()
+        message(FATAL_ERROR "Could not find libraries for Catch2.")
+    endif()
+
+    # Set up the unified unit test target
+    set(UNIFIED_UNIT_TEST_TARGET "unit-test-all")
+    add_executable(${UNIFIED_UNIT_TEST_TARGET})
+    target_link_libraries(${UNIFIED_UNIT_TEST_TARGET} PRIVATE Catch2::Catch2WithMain)
+    target_compile_features(${UNIFIED_UNIT_TEST_TARGET} PRIVATE cxx_std_20)
+    set_property(
+        TARGET
+            ${UNIFIED_UNIT_TEST_TARGET}
+        PROPERTY
+            RUNTIME_OUTPUT_DIRECTORY
+                ${CMAKE_BINARY_DIR}/testbin
+    )
+endif()
+
 include(ystdlib-cpp-helpers)
 
 add_subdirectory(src/ystdlib)
-
-add_executable(unitTest)
-target_sources(unitTest PRIVATE src/main.cpp)
-target_link_libraries(
-    unitTest
-    PRIVATE
-        ystdlib::testlib
-        Catch2::Catch2WithMain
-)
-target_compile_features(unitTest PRIVATE cxx_std_20)

README.md

@@ -28,11 +28,32 @@ git submodule update --init --recursive
 ```
 
 ## Building
-To build all targets in `ystdlib-cpp`:
+To build all targets:
 ```shell
 task build:all
 ```
 
+To build an executable containing all unit tests:
+```shell
+task build:unit-test-all
+```
+
+To build an executable containing a single library's unit tests:
+```shell
+task build:unit-test-<lib_name>
+```
+
+## Testing
+To build and run all unit tests:
+```shell
+task test-all
+```
+
+To build and run unit tests for a specific library:
+```shell
+task test-<lib_name>
+```
+
 ## Linting
 Before submitting a pull request, ensure you’ve run the linting commands below and have fixed all
 violations and suppressed all warnings.

src/ystdlib/testlib/CMakeLists.txt

@@ -1 +1 @@
-cpp_library(NAME testlib NAMESPACE ystdlib)
+cpp_library(NAME testlib NAMESPACE ystdlib TESTS_SOURCES test-hello.cpp)

src/main.cpp renamed to src/ystdlib/testlib/test-hello.cpp

@@ -10,6 +10,10 @@ vars:
   G_BUILD_DIR: "{{.ROOT_DIR}}/build"
   G_CPP_SRC_DIR: "{{.ROOT_DIR}}/src"
   G_DEPS_DIR: "{{.G_BUILD_DIR}}/deps"
+  G_TEST_BIN_DIR: "{{.G_BUILD_DIR}}/testbin"
+  G_TEST_TARGET_SUFFIXES:
+    - "all"
+    - "testlib"
 
 tasks:
   clean:
@@ -23,3 +27,13 @@ tasks:
     run: "once"
     cmds:
       - "mkdir -p '{{.G_BUILD_DIR}}'"
+
+  test-*:
+    desc: "Runs unit tests for the specified test target."
+    vars:
+      TEST_TARGET: >-
+        {{printf "unit-test-%s" (index .MATCH 0)}}
+    deps:
+      - "build:{{.TEST_TARGET}}"
+    cmds:
+      - "{{.G_TEST_BIN_DIR}}/{{.TEST_TARGET}}"

taskfile.yaml

@@ -8,14 +8,46 @@ vars:
 
 tasks:
   all:
-    desc: "Builds ystdlib-cpp."
+    desc: "Builds all of ystdlib-cpp."
     deps:
       - "init"
     cmds:
       - task: ":utils:cmake-build"
         vars:
           BUILD_DIR: "{{.G_BUILD_DIR}}"
 
+  target-*:
+    desc: "Builds a CMake target."
+    vars:
+      TARGET: "{{index .MATCH 0}}"
+    deps:
+      - "init"
+    cmds:
+      - task: ":utils:cmake-build"
+        vars:
+          BUILD_DIR: "{{.G_BUILD_DIR}}"
+          TARGETS:
+            - "{{.TARGET}}"
+
+  unit-test-*:
+    desc: "Builds the specified unit test target."
+    vars:
+      TARGET_SUFFIX: >-
+        {{index .MATCH 0}}
+      TARGET_NAME: >-
+        {{printf "unit-test-%s" .TARGET_SUFFIX}}
+    preconditions:
+      - sh: >-
+          {{has .TARGET_SUFFIX .G_TEST_TARGET_SUFFIXES}}
+        msg: |-
+          {{.TARGET_NAME}} is not a valid unit test target!
+          List of unit test targets:
+          {{- range .G_TEST_TARGET_SUFFIXES }}
+            unit-test-{{.}}
+          {{- end}}
+    cmds:
+      - task: "target-{{.TARGET_NAME}}"
+
   clean:
     desc: "Removes all built artifacts."
     deps: